The electric machine serves for transforming electrical energy into kinetic energy or vice versa. In the former case, the electric machine is operated as a motor, in the latter case as a generator. The electric machine is present, for example, in the form of a traction machine of a motor vehicle. Accordingly, it serves for the propulsion of the motor vehicle, i.e., the providing of a torque directed at driving the motor vehicle. The electric machine comprises the stator and the rotor, which are arranged in the machine housing. The rotor is mounted and can rotate relative to the stator about the axis of rotation.
Heat accrues during the operation of the electric machine and this must be discharged by means of a coolant, especially in electric machines with high power density. For this reason, the machine housing comprises the coolant inlet port and the coolant outlet port. Through the coolant inlet port, coolant can be supplied to the machine housing. Through the coolant outlet port, on the other hand, the coolant can be drained from the machine housing.
In the prior art, the document EP 3 054 565 A1 is known, for example. This relates to a cooling arrangement for the cooling of stator windings of a generator stator arranged in a generator housing, said stator having a plurality of axial cooling ducts, wherein an axial cooling duct extends between windings that are arranged on adjacent stator teeth. Furthermore, a cover device is provided in order to separate the axial cooling ducts from an air gap of the generator, wherein an axial cover of the cover device comprises at least one inlet opening, which connects the air gap to an axial cooling duct. Finally, a flow device is provided to bring a gaseous coolant flow into the air gap and the axial cooling ducts.